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On the hydro-mechanical behavior of ancient railway flatforms in term of reinforcement by soil-mixing / Étude du comportement hydromécanique des plateformes ferroviaires anciennes en vue du renforcement par le 'soil-mixing'Duong, Trong Vinh 25 November 2013 (has links)
Le présent travail porte sur le comportement des plates-formes ferroviaires anciennes en France. Tout d'abord, une étude statistique a été menée sur les problèmes survenus dans l'ensemble du réseau ferroviaire français. L'analyse montre l'importance particulière de la qualité du sol support pour la performance de la sous-structure et pour la tenue géométrique des voies. Ensuite, une ligne ferroviaire ancienne située à l'Ouest de la France a été étudiée spécifiquement. Les analyses montrent que la vitesse de dégradation de cette ligne est en corrélation avec les différents paramètres tels que la nature de sol support, l'épaisseur des couches de la sous-structure. Une tendance d'augmentation de la vitesse de dégradation avec la diminution de l'épaisseur de la couche intermédiaire est identifiée. Cette couche as un impact positif puisqu'elle réduit les contraintes appliquées au sol support. Le comportement hydromécanique du sol de la couche intermédiaire dans des conditions différentes (teneur en eau, teneur en particules fines, charge, nombre de cycles) a été étudié. Des essais triaxiaux et des essais de colonne d'infiltration ont été réalisés à cette fin. En analysant les propriétés de résistance au cisaillement, la déformation axiale permanente et le module réversible, on a constaté que les effets de la teneur en eau et de la teneur en fines doivent être pris en compte ensemble. Une augmentation de teneur en fines dans la couche intermédiaire présente un impact positif à l'état non saturé grâce à l'effet de la succion, mais un impact négatif à l'état saturé. Les essais de colonne d'infiltration avec des cycles de séchage/humidification ont montré que la conductivité hydraulique du sol est gouvernée par la fraction de fines et qu'elle ne change pas significativement avec la teneur en fines. Afin d'étudier les mécanismes de la création de la couche intermédiaire et de remontée boueuse, un modèle physique de 550 mm de diamètre intérieur a été développé. Des échantillons de sol qui représentent la sous-structure ferroviaire ancienne avec une couche de ballast posée sur une couche de limon artificielle (mélange de sable concassé et du kaolin) ont été testés. Les effets des charges monotones et cycliques, de la teneur en eau et de la masse volumique sèche du sol support ont été étudiés. Il a été constaté que la pression interstitielle développée dans le sol support et la rigidité du sol support sont des facteurs clés pour la migration des particules fines ou la création de la couche intermédiaire/la remontée boueuse. L'eau est la condition nécessaire, mais c'est la compressibilité du sol support qui gouverne le phénomène à se produire / The present work deals with the behavior of ancient railway sub-structure in France. A statistical study was firstly undertaken on problems occurred in the whole ancient French railway network. The analysis evidenced the particular importance of sub-grade quality for the performance of the sub-structure and the track geometry. Afterwards, an ancient railway line in the West of France was investigated. The analysis showed that the degradation speed of this line was correlated with different parameters such as the nature of sub-grades and the thickness of different layers. An increase trend of degradation speed with the increase in interlayer thickness was identified. The interlayer has a positive impact since it reduces the train-induced stress applied to the sub-grade. The hydro-mechanical behavior of interlayer soil under different conditions (water content, fines content, stress, number of cycles) was investigated. A set of triaxial tests and infiltration tests were performed for this purpose. By analyzing the shear strength properties, the permanent axial strain and the resilient modulus of interlayer soil, we found that the water content and the fines content must be considered together. Adding more fines into the interlayer presents a positive impact under unsaturated conditions thanks to the suction effect, but a negative impact under saturated conditions. The infiltration column tests with drying/wetting cycles showed that the hydraulic conductivity of interlayer soil is governed by fines fraction but did not change significantly with fines content. In order to study the mechanism of interlayer creation and mud pumping, a physical model of 550 mm inner diameter was developed. Soil samples representing the ancient French railway substructure with a ballast layer overlying an artificial silt layer (mixture of crushed sand and kaolin were tested. The effects of monotonic and cyclic loadings, water content and dry unit mass of sub-soil were investigated. It was found that the pore water pressure developed in the sub-soil and the sub-soil stiffness are the key factors for the migration of fine particles or the creation of interlayer/mud pumping. Water is the necessary condition, but it is the soil compressibility that governs the phenomenon to occur
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SMUTS : En sociosemiotisk analys av Balenciagas "The Mud Show" 2022 utifrån Pierre Bourdieus teori om kapital samt nutida mediala representationer av kriget i Ukraina. / DIRT : A sociosemiotic analysis of Balenciaga's "The Mud Show" 2022 based on Pierre Bourdieu’s theory of capital and contemporary media representations of the war in Ukraine.Rosberg, Andrea January 2023 (has links)
The main purpose of this study is to examine how the media representation of the war in Ukraine is portrayed in Balenciaga’s runway for "Summer 23" collection in Paris Fashion Week 2022. To reach the objective of this study I used an approach based on a qualitative method with support from theories concerning socio-semiotics, Pierre Bourdieu’s theory of capital, provocation and taste. The material, based on video sequences and screenshots from the runway-show, are analyzed in correlation to the contemporary social and cultural context of a westernized perspective. The outcome of this study indicates that Balenciaga, as a luxurious brand with high levels of all forms of capital, alludes to the media’s representation of war as a means of provocation, which makes the "good taste" that they possess change. / The primary aim with my Media Production is to create a visual material whose purpose is to emotionally touch the intended target group to click on the Action for Happiness website and to learn more about how one can live to achieve a happier life. My animated introductory video is meant to be an entry to the "10 Key Words for a Happier Life" page on the website.
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L'utilisation de l'argile dans l'architecture domestique et publique en Grèce antique : une étude d'un inventaire de sites archéologiquesGiroux, Sabrina 01 1900 (has links)
Ce mémoire est une exploration du thème de l'utilisation de l'argile en architecture domestique et publique en Grèce Antique. À travers un inventaire de sites archéologiques, nous examinerons les différents vestiges présents qui démontrent l'utilisation de l'argile dans l'architecture, par exemple dans la production de briques d'argiles crues et dans les élévations en terre compactée. Ces vestiges sont très peu représentés archéologiquement et nous explorerons les raisons et questionnements amenés par cette faible présence. / This thesis is an exploration about the use of earth, more precisely clay, in domestic and public architecture in ancient Greece. In a first time, we will review some publications about clay and the different uses that was made of it during Antiquity. Then, we will present some archaeological sites that show remains in clay, more precisely wall architecture of mud-brick, and adobe. This kind of remains is really rare in Greek archaeology, and through this thesis we will see why, try to solve some questions about it, and finally, talk about the future and conservation of these remains.
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Modélisation numérique de la mise en suspension de sédiments cohésifs par instabilités de cisaillement / Numerical modeling of cohesive sediment suspension by shear instabilitiesHarang, Alice 22 February 2013 (has links)
Ce travail numérique porte sur le comportement de la lutocline (interface entre l'eau et la vase fluide) en écoulement cisaillé et vise à une meilleure compréhension des mécanismes de remise en suspension de sédiments cohésifs. La crème de vase, ou vase partiellement solidifiée, est modélisée par un fluide homogène équivalent miscible dans l'eau, de rhéologie newtonienne ou viscoplastique. Une étude de l'hydrodynamique de cet écoulement stratifié en densité ainsi qu'en viscosité est ensuite proposée. Considérant une crème de vase initialement non-turbulente, l'étude se focalise sur le développement des instabilités au niveau de la lutocline et de la transition vers une couche de mélange turbulente. La particularité de cet écoulement réside dans la forte viscosité de vase et son seuil de mise en mouvement lorsqu'elle présente un caractère viscoplastique. Une étude de stabilité linéaire permet d'évaluer l'influence des différents paramètres de l'écoulement, notamment les stratifications en densité et en viscosité. La stratification en viscosité augmente sensiblement le taux de croissance de l'instabilité pour des nombres de Reynolds intermédiaires. L'évolution non-linéaire de l'écoulement est ensuite étudiée en utilisant des simulations numériques directes, la stratification en viscosité entrainant un épaississement de la couche de mélange finale. Enfin, des simulations numériques directes basées sur un modèle de fluide de Bingham régularisé permettent d'étudier l'influence de la contrainte seuil sur le développement de l'instabilité. / This numerical study focuses on the behavior of the lutocline in a shear flow and aims to better understand the mechanism of resuspension of cohesive sediment. Mud flow, or mud partially consolidated, is modeled by an equivalent homogenous fluid miscible in water, with newtonian or viscoplastic rheology. A study of the hydrodynamics of this shear flow, stratified both in density and viscosity, is presented. Considering an initially laminar mud flow, the focus of the study is on the development of instabilities on the lutocline and the transition to a turbulent mixing layer. The specificity of this flow lies on the large viscosity of the mud and its threshold to be put in motion, when it presents a viscoplastic feature. A linear stability study assesses the influence of the various parameters of the flow, especially of density and viscosity stratification. The viscosity stratification slightly increases the growth rate of the instability for intermediate Reynolds numbers. Then, the non linear evolution of the flow is studied by using direct numerical simulations, viscous stratification leading to a thicker mixing layer. At last, direct numerical simulations based on a Bingham regularized model, permits to study the influence of the critical strain on the development of the instability.
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[en] NON NEWTONIAN FLOW IN ECCENTRIC ANNULAR SPACE WITH ROTATING INNER CYLINDER / [pt] ESCOAMENTO DE FLUIDO NÃO NEWTONIANO EM ESPAÇO ANULAR EXCÊNTRICO COM ROTAÇÃO DO CILINDRO INTERNOINAE RODRIGUES DE ALMEIDA 09 April 2014 (has links)
[pt] O presente trabalho apresenta um modelo simplificado baseado na teoria de lubrificação e conceito de viscosidade equivalente para estudar o escoamento dos fluidos de perfuração através de um espaço anular excêntrico com rotação da coluna de perfuração. Em razão do comportamento não Newtoniano destes fluidos, é significativa a influência da rotação da coluna na perda de carga, já que a viscosidade dos fluidos varia com a taxa de deformação imposta. Uma completa análise deste problema requer uma solução tridimensional da equação de conservação de quantidade de movimento de fluidos não Newtonianos, cuja solução é extremamente cara computacionalmente, tornando necessário o desenvolvimento de modelos simplificados que descrevam bem os principais fenômenos observados nestes escoamentos. No modelo proposto, as equações que governam o escoamento são simplificadas pela teoria da lubrificação em coordenadas cilíndricas. Desta forma, o escoamento tridimensional é descrito por uma única equação diferencial bidimensional para o campo de pressão. O comportamento mecânico do fluido é avaliado através do método da Viscosidade Newtoniana Equivalente. O modelo proposto foi validado a partir de soluções numéricas para o modelo completo, disponíveis na literatura, avaliando a precisão das simplificações adotadas. Os resultados mostram o intervalo no qual o modelo simplificado é preciso e apresentam o efeito das propriedades dos fluidos, da geometria do poço e da rotação da coluna na perda de carga do escoamento.O presente trabalho apresenta um modelo simplificado baseado na teoria de lubrificação e conceito de viscosidade equivalente para estudar o escoamento dos fluidos de perfuração através de um espaço anular excêntrico com rotação da coluna de perfuração. Em razão do comportamento não Newtoniano destes fluidos, é significativa a influência da rotação da coluna na perda de carga, já que a viscosidade dos fluidos varia com a taxa de deformação imposta. Uma completa análise deste problema requer uma solução tridimensional da equação de conservação de quantidade de movimento de fluidos não Newtonianos, cuja solução é extremamente cara computacionalmente, tornando necessário o desenvolvimento de modelos simplificados que descrevam bem os principais fenômenos observados nestes escoamentos. No modelo proposto, as equações que governam o escoamento são simplificadas pela teoria da lubrificação em coordenadas cilíndricas. Desta forma, o escoamento tridimensional é descrito por uma única equação diferencial bidimensional para o campo de pressão. O comportamento mecânico do fluido é avaliado através do método da Viscosidade Newtoniana Equivalente. O modelo proposto foi validado a partir de soluções numéricas para o modelo completo, disponíveis na literatura, avaliando a precisão das simplificações adotadas. Os resultados mostram o intervalo no qual o modelo simplificado é preciso e apresentam o efeito das propriedades dos fluidos, da geometria do poço e da rotação da coluna na perda de carga do escoamento.O presente trabalho apresenta um modelo simplificado baseado na teoria de lubrificação e conceito de viscosidade equivalente para estudar o escoamento dos fluidos de perfuração através de um espaço anular excêntrico com rotação da coluna de perfuração. Em razão do comportamento não Newtoniano destes fluidos, é significativa a influência da rotação da coluna na perda de carga, já que a viscosidade dos fluidos varia com a taxa de deformação imposta. Uma completa análise deste problema requer uma solução tridimensional da equação de conservação de quantidade de movimento de fluidos não Newtonianos, cuja solução é extremamente cara computacionalmente, tornando necessário o desenvolvimento de modelos simplificados que descrevam bem os principais fenômenos observados nestes escoamentos. No modelo proposto, as equações que governam o escoamento são simplificadas pela teoria da lubrificação em coordenadas cilíndricas. Desta forma, o escoamento tridimensional é descrito por uma única equação diferencial bidimensional para o campo de pressão. O comportamento mecânico do fluido é avaliado através do método da Viscosidade Newtoniana Equivalente. O modelo proposto foi validado a partir de soluções numéricas para o modelo completo, disponíveis na literatura, avaliando a precisão das simplificações adotadas. Os resultados mostram o intervalo no qual o modelo simplificado é preciso e apresentam o efeito das propriedades dos fluidos, da geometria do poço e da rotação da coluna na perda de carga do escoamento. / [en] In this work a simplified model based on the Lubrication Theory and on the equivalent viscosity is presented to study the drilling fluid flow dynamics through an eccentric annular space with rotation of the drilling column. As a result of the non-Newtonian behavior of the fluid, the rotation of the column has a significant impact on the pressure drop since the viscosity of the fluids is a function of the strain rate applied. A complete analysis of this problem requires a tridimensional solution of the equation of momentum conservation, which makes the solution computationally expensive. For such, simplified accurate models that describe the main phenomena observed have to be developed. On the proposed model, the flow dynamics equations are simplified by the Lubrication Theory in cylindrical coordinates. Therefore, the tridimensional flow is described by one single two dimensional equation for the pressure field. The mechanical behaviour of the fluid is evaluated through the Equivalent Newtonian Viscosity method. The proposed model, as well as the accuracy of the simplifications used, was validated by comparison with numerical solutions of the complete set of equations available on the literature. The results show the range in which the proposed simplified model is accurate and presents the effects of the fluids properties, well geometry and column rotation on the pressure loss.
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"Efeito antiinflamatório da lama negra de Peruíbe em diferentes modelos experimentais de artrite" / The anti-inflammatory efficacy of mud therapy (peruíbe, sp, brazil) on differents experimental models of arthritisBritschka, Zelia Maria Nogueira 22 February 2006 (has links)
Investigar a eficácia da lama negra brasileira como tratamento para inflamação em modelos experimentais de artrite. O efeito antiinflamatório de aplicações de lama foi comparado ao tratamento com água aquecida e ausência de tratamento em modelos experimentais de artrite e osteoartrite induzidas em coelhos e em ratos, visando parâmetros inflamatórios e cartilagem. O tratamento com lama melhorou a infiltração de leucócitos e exerceu um efeito protetor parcial na sinóvia e cartilagem. Nossos resultados sugerem que a lama brasileira apresenta efeito antiinflamatório e pode ser útil como um método complementar ao tratamento de pacientes com doenças articulares crônicas / Investigate the effectiveness of a Brazilian black mud as treatment for inflammation in experimental models of arthritis. Effects of mud applications was compared with warm water and no treatment in experimental models of arthritis and osteoarthritis induced in rabbits and in rats, regarding inflammatory parameters and cartilage. Treatment with mud impaired leukocyte infiltration which was followed by a partial protective effect on synovium and cartilage. Our results show that Brazilian mud presents an anti-inflammatory effect and can be useful as a complementary approach to treat patients with chronicle articular diseases
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Observação do transporte de sedimentos em suspensão ao longo do Canal Norte do rio Amazonas durante condições de baixa descarga (outubro 2008) / Observation of suspended sediment transport along North Channel of Amazon river during low discharge (October 2008)Edgard Villarinho Garcia Neto 21 October 2011 (has links)
Fundação Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro / The Amazon river, located in northernBrazil, discharges between 80,000 and 250,000 m3s-1 of water onto the adjacent shelf, creating a plume of brackish water that extends hundreds of kilometers away from the river mouth. This river also carries a large amount of fine sediments to the ocean where fluid mud has been found in the topset and upper foreset layers of the subaqueous delta formed on the mid-shelf. One of the main goals of this dissertation is to describe how turbulence and suspended sediment concentration vary along the Northern Channel of the Amazon river. Water column measurements were carried out in October 2008 at six anchor stations (P1, P3, P5, P6, P8 e P9) located seaward of the river mouth; P1 and P9 were 125 km apart. Each station was occupied during 13 hours during which current speed and direction were continuously sampled with a 600 kHz Teledyne-RDI ADCP; hourly profiles of temperature, salinity, turbidity and depth were also obtained. Water samples were collected for determination of Suspended Particulate Matter (SPM) concentration and calibration of the turbidity sensor. Current speed reached values above 1.5 m s1 in the along-channel direction (NE-SW); a remarkable ebb-flood asymmetry was observed and flows were strongly ebb-dominated. Throughout the water column, SPM concentration at stations P1 and P3 varied between 100 and 300 mg L1 in association with the presence of freshwater. In contrast, a strong salinity gradient was observed between stations P6 and P9, coinciding with the occurrence of concentrations of SPM above 10 g L-1 (fluid mud). At stations P3, P5 and P6, interface between freshwater from the Amazon river and salt water from the continental shelf, shear stresses wereestimated through four diferents methods: Reynolds, Turbulent Kinetic Energy (TKE), modified TKE and Quadratic Law; in the nearbed region (3 mab) the computed values varied between 0 and 3 Pa. At the three stations (P3, P5 and P6) the lowest and the highest shear stress values were obtained through, respectively, the Reynolds and the TKE methods. Over the whole water column turbulence intensity was estimated through the standard deviation of the turbulent component of the along-channel current velocity (root-mean square of u); from these values, it was estimated the turbulent dissipation of energy (G), whose values at 3 mab varied between zero and 20 s1.
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Structure et fonctionnement des communautés de faune benthique au cours du développement d'une mangrove de Guyane française / Structure and functioning of the benthic faunal communities during mangroves development in French GuianaAschenbroich, Adélaïde 15 September 2016 (has links)
La compréhension des processus contrôlant le fonctionnement des mangroves est capitale au vu des services socio-économiques/écosystémiques rendus par ces écosystèmes et des menaces qu’ils subissent. En Guyane Française, les mangroves se développent rapidement en réponse aux contraintes sédimentaires récurrentes induites naturellement par les apports sédimentaires amazoniens. Cette thèse étudie la structure et la composition de trois classes de taille de communautés benthique (méso, macro, mégafaune), et les activités de bioturbation associées (remaniement sédimentaire biologique : RS, terriers) dans les jeunes stades de mangrove. 51 taxons de méso-macrofaune et 12 espèces de crabes (mégafaune) ont été identifiés. Bien que la biodiversité benthique soit spécifique à l'âge de la mangrove, des taxons tolèrent les modifications brusques du milieu, et cette persistance maintient des fonctions clés du remaniement sédimentaire tout au long du développement des mangroves. L’intensité du RS varie le long de ce gradient (21-146 g PS.m-2.cycle tidal-1). Si les crabes dominent le RS, cette thèse souligne la contribution effective de la méso-macrofaune aux transports particulaires. Les communautés benthiques montrent des capacités de bioturbation adaptées aux instabilités récurrentes du littoral. Les variations du RS au cours du temps pourraient indiquer l’état fonctionnel des mangroves. Cette étude conclut que l’hétérogénéité morpho-sédimentaire au sein des jeunes stades de mangroves influence la structuration spatiale des crabes, le remaniement sédimentaire qu’ils induisent, et la morphologie des terriers. Les microhabitats devraient être considérés lors de l'évaluation du rôle fonctionnel de la faune benthique des mangroves. / Understanding the processes that control mangroves functioning is essential regarding the socioeconomic/ecosystemic services these ecosystems provide and the increasing threats they suffer. In French Guiana, mangroves grow rapidly in response to natural sedimentary perturbations caused by sediment inputs from the Amazon River. This thesis characterizes the structure and the composition of benthic fauna communities (three size classes: meso-, macro- and megafauna) and the associated bioturbation activities (biological sediment reworking: SR, burrows) in mangrove early growth stages. 51 meso- macrofaunal taxa and 12 crab (megafauna) species were identified.Despite a mangrove age specific biodiversity, some taxa tolerate abrupt environmental changes, and such persistence maintains key sediment reworking functions along mangrove development.The SR intensity varies along this gradient from 21 to 146 g DW.m-2.tidal cycle-1. Burrower crabs dominate the SR but this thesis also outlines the non-negligible contribution of smaller-sized (meso- and macrofauna) organisms to particulate transport. Benthic communities’ bioturbation capacities are adapted to recurrent environmental instabilities. Changes of the biologicallyinduced SR may be used as a proxy of the functional status of mangrove ecosystems. This study concludes that morpho-sedimentary heterogeneity of early-growth mangrove stages influences crab spatial structuration, the crab-induced sediment reworking and burrow shapes. Thus, microhabitat specificities should be considered when evaluating the role of benthic fauna in mangroves ecosystem functioning.
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"Efeito antiinflamatório da lama negra de Peruíbe em diferentes modelos experimentais de artrite" / The anti-inflammatory efficacy of mud therapy (peruíbe, sp, brazil) on differents experimental models of arthritisZelia Maria Nogueira Britschka 22 February 2006 (has links)
Investigar a eficácia da lama negra brasileira como tratamento para inflamação em modelos experimentais de artrite. O efeito antiinflamatório de aplicações de lama foi comparado ao tratamento com água aquecida e ausência de tratamento em modelos experimentais de artrite e osteoartrite induzidas em coelhos e em ratos, visando parâmetros inflamatórios e cartilagem. O tratamento com lama melhorou a infiltração de leucócitos e exerceu um efeito protetor parcial na sinóvia e cartilagem. Nossos resultados sugerem que a lama brasileira apresenta efeito antiinflamatório e pode ser útil como um método complementar ao tratamento de pacientes com doenças articulares crônicas / Investigate the effectiveness of a Brazilian black mud as treatment for inflammation in experimental models of arthritis. Effects of mud applications was compared with warm water and no treatment in experimental models of arthritis and osteoarthritis induced in rabbits and in rats, regarding inflammatory parameters and cartilage. Treatment with mud impaired leukocyte infiltration which was followed by a partial protective effect on synovium and cartilage. Our results show that Brazilian mud presents an anti-inflammatory effect and can be useful as a complementary approach to treat patients with chronicle articular diseases
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Approche granulaire et colloïdale du matériau terre pour la construction / Granular and colloïdal approach of earthen building materialAnger, Romain 20 December 2011 (has links)
La terre crue est un des matériaux les plus utilisés au monde pour bâtir. Chaque terre est un mélange de grains de différentes tailles (cailloux, graviers, sables, silts et argiles) en proportions variées. Les particules les plus fines, qui constituent le liant du matériau, se différencient des autres grains par leur petite taille, à laquelle est associée des propriétés colloïdales lorsqu’elles sont mélangées à l’eau. L’argile, au sens granulométrique (particules inférieures à deux microns), contient généralement un mélange d’argiles, au sens minéralogique (phyllosilicates hydratés), d’oxydes de fer, d’aluminium et de silicium. Pour comprendre ce matériau de construction, la terre est envisagée dans un premier temps comme une matière en grains. La physique des milieux granulaires secs et la physique des milieux granulaires humides sont explorées afin de décrire les comportements physiques de cette matière. Des techniques de construction innovantes, qui découlent de cette compréhension, sont présentées. Dans un deuxième temps, l’argile est envisagée comme une matière colloïdale. Comme beaucoup de systèmes naturels, le liant argileux est un mélange de particules aux propriétés de surface différentes, contenant à la fois des charges permanentes négatives et des charges variables avec le pH et la force ionique. Ces systèmes mixtes sont dits hétérocoagulés. Des pistes de recherche, qui découlent de cette compréhension, sont présentées. / Raw earth is one of the most used building material in the world. Each earthen material is a mix of different sizes grains (stones, gravels, sands, silts and clays) in various proportions. The finest particles, which constitute the binding material, differ from other grains by their small size, which is associated with colloidal properties when mixed with water. Clay, as defined by size (particles smaller than two microns), usually contains a mixture of clays, as defined by mineralogy (hydrated phyllosilicates), with iron, aluminum and silicium oxides. To understand this building material, earthen material is considered initially as a granular material. Physics of dry granular media and physics of wet granular media are explored in order to describe the physical behavior of this material. Innovative building systems, which come from this understanding, are presented. In a second step, clay is considered as a colloidal material. Like many natural systems, clay binder is a mixture of particles with different surface properties, containing both permanent negative charges and variable charges, depending of pH and ionic strength. These mixed systems are called heterocoagulated systems. Different sujects for further researches, that follow this understanding, are presented.
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